I listened to the soundclip - it's really not very helpful for the tune as the singer talks more than sings (at least in that very brief clip). But what bit could be made out sounded very similar to the tune of "The Lass of Swansea Town", so that tune could be used.

In the clip, the line "And there are buried secrets far older than human bones" is actually "And there are buried secrets older far than human bones", which does scan better.

I searched to see if there is a real River Wyth and couldn't find one. Does anyone know if there is such a river anywhere?

Joan